add API fallback for engine utils lib

Signed-off-by: Nick Cameron <nrc@ncameron.org>

.eslintignore

@@ -1,3 +1,4 @@
 src/wasm-lib/*
+src/lib/engine-utils/engine.js
 *.typegen.ts
 packages/codemirror-lsp-client/dist/*

.gitignore

@@ -66,3 +66,7 @@ venv
 
 # electron
 out/
+
+# engine wasm utils
+src/lib/engine-utils/engine.wasm
+src/lib/engine-utils/engine.js

e2e/playwright/file-tree.spec.ts

@@ -136,6 +136,9 @@ test.describe('when using the file tree to', () => {
       )
       await pasteCodeInEditor(kclCube)
 
+      // TODO: We have a timeout of 1s between edits to write to disk. If you reload the page too quickly it won't write to disk.
+      await tronApp.page.waitForTimeout(2000)
+
       await renameFile(fromFile, toFile)
       await tronApp.page.reload()
 
@@ -222,9 +225,11 @@ test.describe('when using the file tree to', () => {
       )
       await pasteCodeInEditor(kclCube)
 
+      // TODO: We have a timeout of 1s between edits to write to disk. If you reload the page too quickly it won't write to disk.
+      await tronApp.page.waitForTimeout(2000)
+
       const kcl1 = 'main.kcl'
       const kcl2 = '2.kcl'
-
       await createNewFileAndSelect(kcl2)
       const kclCylinder = await fsp.readFile(
         'src/wasm-lib/tests/executor/inputs/cylinder.kcl',
@@ -232,6 +237,9 @@ test.describe('when using the file tree to', () => {
       )
       await pasteCodeInEditor(kclCylinder)
 
+      // TODO: We have a timeout of 1s between edits to write to disk. If you reload the page too quickly it won't write to disk.
+      await tronApp.page.waitForTimeout(2000)
+
       await renameFile(kcl2, kcl1)
 
       await test.step(`Postcondition: ${kcl1} still has the original content`, async () => {

src/clientSideScene/CameraControls.ts

@@ -64,6 +64,27 @@ export type ReactCameraProperties =
 
 const lastCmdDelay = 50
 
+class CameraRateLimiter {
+  lastSend?: Date = undefined
+  rateLimitMs: number = 16 //60 FPS
+
+  send = (f: () => void) => {
+    let now = new Date()
+
+    if (
+      this.lastSend === undefined ||
+      now.getTime() - this.lastSend.getTime() > this.rateLimitMs
+    ) {
+      f()
+      this.lastSend = now
+    }
+  }
+
+  reset = () => {
+    this.lastSend = undefined
+  }
+}
+
 export class CameraControls {
   engineCommandManager: EngineCommandManager
   syncDirection: 'clientToEngine' | 'engineToClient' = 'engineToClient'
@@ -77,9 +98,8 @@ export class CameraControls {
   enableRotate = true
   enablePan = true
   enableZoom = true
-  zoomDataFromLastFrame?: number = undefined
+  moveSender: CameraRateLimiter = new CameraRateLimiter()
-  // holds coordinates, and interaction
+  zoomSender: CameraRateLimiter = new CameraRateLimiter()
-  moveDataFromLastFrame?: [number, number, string] = undefined
   lastPerspectiveFov: number = 45
   pendingZoom: number | null = null
   pendingRotation: Vector2 | null = null
@@ -171,6 +191,36 @@ export class CameraControls {
     }
   }
 
+  doMove = (interaction: any, coordinates: any) => {
+    // eslint-disable-next-line @typescript-eslint/no-floating-promises
+    this.engineCommandManager.sendSceneCommand({
+      type: 'modeling_cmd_req',
+      cmd: {
+        type: 'camera_drag_move',
+        interaction: interaction,
+        window: {
+          x: coordinates[0],
+          y: coordinates[1],
+        },
+      },
+      cmd_id: uuidv4(),
+    })
+  }
+
+  doZoom = (zoom: number) => {
+    this.handleStart()
+    // eslint-disable-next-line @typescript-eslint/no-floating-promises
+    this.engineCommandManager.sendSceneCommand({
+      type: 'modeling_cmd_req',
+      cmd: {
+        type: 'default_camera_zoom',
+        magnitude: (-1 * zoom) / window.devicePixelRatio,
+      },
+      cmd_id: uuidv4(),
+    })
+    this.handleEnd()
+  }
+
   constructor(
     isOrtho = false,
     domElement: HTMLCanvasElement,
@@ -258,49 +308,6 @@ export class CameraControls {
       this.onCameraChange()
     }
 
-    // Our stream is never more than 60fps.
-    // We can get away with capping our "virtual fps" to 60 then.
-    const FPS_VIRTUAL = 60
-
-    const doZoom = () => {
-      if (this.zoomDataFromLastFrame !== undefined) {
-        this.handleStart()
-        // eslint-disable-next-line @typescript-eslint/no-floating-promises
-        this.engineCommandManager.sendSceneCommand({
-          type: 'modeling_cmd_req',
-          cmd: {
-            type: 'default_camera_zoom',
-            magnitude:
-              (-1 * this.zoomDataFromLastFrame) / window.devicePixelRatio,
-          },
-          cmd_id: uuidv4(),
-        })
-        this.handleEnd()
-      }
-      this.zoomDataFromLastFrame = undefined
-    }
-    setInterval(doZoom, 1000 / FPS_VIRTUAL)
-
-    const doMove = () => {
-      if (this.moveDataFromLastFrame !== undefined) {
-        // eslint-disable-next-line @typescript-eslint/no-floating-promises
-        this.engineCommandManager.sendSceneCommand({
-          type: 'modeling_cmd_req',
-          cmd: {
-            type: 'camera_drag_move',
-            interaction: this.moveDataFromLastFrame[2] as any,
-            window: {
-              x: this.moveDataFromLastFrame[0],
-              y: this.moveDataFromLastFrame[1],
-            },
-          },
-          cmd_id: uuidv4(),
-        })
-      }
-      this.moveDataFromLastFrame = undefined
-    }
-    setInterval(doMove, 1000 / FPS_VIRTUAL)
-
     setTimeout(() => {
       this.engineCommandManager.subscribeTo({
         event: 'camera_drag_end',
@@ -386,7 +393,9 @@ export class CameraControls {
       if (interaction === 'none') return
 
       if (this.syncDirection === 'engineToClient') {
-        this.moveDataFromLastFrame = [event.clientX, event.clientY, interaction]
+        this.moveSender.send(() => {
+          this.doMove(interaction, [event.clientX, event.clientY])
+        })
         return
       }
 
@@ -459,7 +468,9 @@ export class CameraControls {
 
     if (this.syncDirection === 'engineToClient') {
       if (interaction === 'zoom') {
-        this.zoomDataFromLastFrame = event.deltaY
+        this.zoomSender.send(() => {
+          this.doZoom(event.deltaY)
+        })
       } else {
         // This case will get handled when we add pan and rotate using Apple trackpad.
         console.error(

src/components/FileTree.tsx

@@ -488,6 +488,12 @@ export const FileTreeInner = ({
   // Refresh the file tree when there are changes.
   useFileSystemWatcher(
     async (eventType, path) => {
+      // Our other watcher races with this watcher on the current file changes,
+      // so we need to stop this one from reacting at all, otherwise Bad Things
+      // Happen™.
+      const isCurrentFile = loaderData.file?.path === path
+      const hasChanged = eventType === 'change'
+      if (isCurrentFile && hasChanged) return
       fileSend({ type: 'Refresh' })
     },
     [loaderData?.project?.path, fileContext.selectedDirectory.path].filter(

src/components/ModelingMachineProvider.tsx

@@ -69,7 +69,7 @@ import { exportFromEngine } from 'lib/exportFromEngine'
 import { Models } from '@kittycad/lib/dist/types/src'
 import toast from 'react-hot-toast'
 import { EditorSelection, Transaction } from '@codemirror/state'
-import { useNavigate, useSearchParams } from 'react-router-dom'
+import { useLoaderData, useNavigate, useSearchParams } from 'react-router-dom'
 import { letEngineAnimateAndSyncCamAfter } from 'clientSideScene/CameraControls'
 import { getVarNameModal } from 'hooks/useToolbarGuards'
 import { err, reportRejection, trap } from 'lib/trap'
@@ -84,6 +84,7 @@ import {
 import { submitAndAwaitTextToKcl } from 'lib/textToCad'
 import { useFileContext } from 'hooks/useFileContext'
 import { uuidv4 } from 'lib/utils'
+import { IndexLoaderData } from 'lib/types'
 
 type MachineContext<T extends AnyStateMachine> = {
   state: StateFrom<T>
@@ -116,6 +117,7 @@ export const ModelingMachineProvider = ({
   } = useSettingsAuthContext()
   const navigate = useNavigate()
   const { context, send: fileMachineSend } = useFileContext()
+  const { file } = useLoaderData() as IndexLoaderData
   const token = auth?.context?.token
   const streamRef = useRef<HTMLDivElement>(null)
   const persistedContext = useMemo(() => getPersistedContext(), [])
@@ -409,12 +411,15 @@ export const ModelingMachineProvider = ({
         Make: ({ event }) => {
           if (event.type !== 'Make') return
           // Check if we already have an export intent.
-          if (engineCommandManager.exportIntent) {
+          if (engineCommandManager.exportInfo) {
             toast.error('Already exporting')
             return
           }
           // Set the export intent.
-          engineCommandManager.exportIntent = ExportIntent.Make
+          engineCommandManager.exportInfo = {
+            intent: ExportIntent.Make,
+            name: file?.name || '',
+          }
 
           // Set the current machine.
           machineManager.currentMachine = event.data.machine
@@ -443,12 +448,16 @@ export const ModelingMachineProvider = ({
         },
         'Engine export': ({ event }) => {
           if (event.type !== 'Export') return
-          if (engineCommandManager.exportIntent) {
+          if (engineCommandManager.exportInfo) {
             toast.error('Already exporting')
             return
           }
           // Set the export intent.
-          engineCommandManager.exportIntent = ExportIntent.Save
+          engineCommandManager.exportInfo = {
+            intent: ExportIntent.Save,
+            // This never gets used its only for make.
+            name: '',
+          }
 
           const format = {
             ...event.data,

src/lang/codeManager.ts

@@ -18,6 +18,7 @@ export default class CodeManager {
   #updateState: (arg: string) => void = () => {}
   private _currentFilePath: string | null = null
   private _hotkeys: { [key: string]: () => void } = {}
+  private timeoutWriter: ReturnType<typeof setTimeout> | undefined = undefined
 
   constructor() {
     if (isDesktop()) {
@@ -115,7 +116,11 @@ export default class CodeManager {
 
   async writeToFile() {
     if (isDesktop()) {
-      setTimeout(() => {
+      // Only write our buffer contents to file once per second. Any faster
+      // and file-system watchers which read, will receive empty data during
+      // writes.
+      clearTimeout(this.timeoutWriter)
+      this.timeoutWriter = setTimeout(() => {
         // Wait one event loop to give a chance for params to be set
         // Save the file to disk
         this._currentFilePath &&
@@ -126,7 +131,7 @@ export default class CodeManager {
               console.error('error saving file', err)
               toast.error('Error saving file, please check file permissions')
             })
-      })
+      }, 1000)
     } else {
       safeLSSetItem(PERSIST_CODE_KEY, this.code)
     }

src/lang/std/engineConnection.ts

@@ -50,6 +50,11 @@ export enum ExportIntent {
   Make = 'make',
 }
 
+export interface ExportInfo {
+  intent: ExportIntent
+  name: string
+}
+
 type ClientMetrics = Models['ClientMetrics_type']
 
 interface WebRTCClientMetrics extends ClientMetrics {
@@ -1354,7 +1359,7 @@ export class EngineCommandManager extends EventTarget {
    * export in progress. Otherwise it is an enum value of the intent.
    * Another export cannot be started if one is already in progress.
    */
-  private _exportIntent: ExportIntent | null = null
+  private _exportInfo: ExportInfo | null = null
   _commandLogCallBack: (command: CommandLog[]) => void = () => {}
 
   subscriptions: {
@@ -1410,12 +1415,12 @@ export class EngineCommandManager extends EventTarget {
     (() => {}) as any
   kclManager: null | KclManager = null
 
-  set exportIntent(intent: ExportIntent | null) {
+  set exportInfo(info: ExportInfo | null) {
-    this._exportIntent = intent
+    this._exportInfo = info
   }
 
-  get exportIntent() {
+  get exportInfo() {
-    return this._exportIntent
+    return this._exportInfo
   }
 
   start({
@@ -1607,7 +1612,7 @@ export class EngineCommandManager extends EventTarget {
           // because in all other cases we send JSON strings. But in the case of
           // export we send a binary blob.
           // Pass this to our export function.
-          if (this.exportIntent === null || this.pendingExport === undefined) {
+          if (this.exportInfo === null || this.pendingExport === undefined) {
             toast.error(
               'Export intent was not set, but export data was received'
             )
@@ -1617,7 +1622,7 @@ export class EngineCommandManager extends EventTarget {
             return
           }
 
-          switch (this.exportIntent) {
+          switch (this.exportInfo.intent) {
             case ExportIntent.Save: {
               exportSave(event.data, this.pendingExport.toastId).then(() => {
                 this.pendingExport?.resolve(null)
@@ -1625,21 +1630,22 @@ export class EngineCommandManager extends EventTarget {
               break
             }
             case ExportIntent.Make: {
-              exportMake(event.data, this.pendingExport.toastId).then(
+              exportMake(
-                (result) => {
+                event.data,
+                this.exportInfo.name,
+                this.pendingExport.toastId
+              ).then((result) => {
                 if (result) {
                   this.pendingExport?.resolve(null)
                 } else {
                   this.pendingExport?.reject('Failed to make export')
                 }
-                },
+              }, this.pendingExport?.reject)
-                this.pendingExport?.reject
-              )
               break
             }
           }
           // Set the export intent back to null.
-          this.exportIntent = null
+          this.exportInfo = null
           return
         }
 
@@ -1953,15 +1959,15 @@ export class EngineCommandManager extends EventTarget {
       return Promise.resolve(null)
     } else if (cmd.type === 'export') {
       const promise = new Promise<null>((resolve, reject) => {
-        if (this.exportIntent === null) {
+        if (this.exportInfo === null) {
-          if (this.exportIntent === null) {
+          if (this.exportInfo === null) {
             toast.error('Export intent was not set, but export is being sent')
             console.error('Export intent was not set, but export is being sent')
             return
           }
         }
         const toastId = toast.loading(
-          this.exportIntent === ExportIntent.Save
+          this.exportInfo.intent === ExportIntent.Save
             ? EXPORT_TOAST_MESSAGES.START
             : MAKE_TOAST_MESSAGES.START
         )
@@ -1975,7 +1981,7 @@ export class EngineCommandManager extends EventTarget {
             resolve(passThrough)
           },
           reject: (reason: string) => {
-            this.exportIntent = null
+            this.exportInfo = null
             reject(reason)
           },
           commandId: command.cmd_id,

src/lang/wasm.ts

@@ -110,6 +110,7 @@ const initialise = async () => {
     const fullUrl = wasmUrl()
     const input = await fetch(fullUrl)
     const buffer = await input.arrayBuffer()
+
     return await init(buffer)
   } catch (e) {
     console.log('Error initialising WASM', e)

src/lib/constants.ts

@@ -92,6 +92,7 @@ export const MAKE_TOAST_MESSAGES = {
   NO_MACHINE_API_IP: 'No machine api ip available',
   NO_CURRENT_MACHINE: 'No current machine available',
   NO_MACHINE_ID: 'No machine id available',
+  NO_NAME: 'No name provided',
   ERROR_STARTING_PRINT: 'Error while starting print',
   SUCCESS: 'Started print successfully',
 }

src/lib/engineUtils.ts

@@ -0,0 +1,31 @@
+import EngineUtils from '@engine-utils'
+
+type KCEngineUtilsEvaluatePath = {
+  (sketch: string, t: number): string
+}
+let kcEngineUtilsEvaluatePath: KCEngineUtilsEvaluatePath
+
+export async function init() {
+  return await new Promise((resolve, reject) => {
+    try {
+      EngineUtils().then((module) => {
+        kcEngineUtilsEvaluatePath = module.cwrap(
+          'kcEngineUtilsEvaluatePath',
+          'string',
+          ['string', 'number']
+        )
+        resolve(true)
+      })
+    } catch (e) {
+      reject(e)
+    }
+  })
+}
+
+export async function getTruePathEndPos(sketch: string) {
+  if (!kcEngineUtilsEvaluatePath) {
+    await init()
+  }
+
+  return kcEngineUtilsEvaluatePath(sketch, 1.0)
+}

src/lib/exportMake.ts

@@ -8,8 +8,15 @@ import { MAKE_TOAST_MESSAGES } from './constants'
 // Make files locally from an export call.
 export async function exportMake(
   data: ArrayBuffer,
+  name: string,
   toastId: string
 ): Promise<Response | null> {
+  if (name === '') {
+    console.error(MAKE_TOAST_MESSAGES.NO_NAME)
+    toast.error(MAKE_TOAST_MESSAGES.NO_NAME, { id: toastId })
+    return null
+  }
+
   if (machineManager.machineCount() === 0) {
     console.error(MAKE_TOAST_MESSAGES.NO_MACHINES)
     toast.error(MAKE_TOAST_MESSAGES.NO_MACHINES, { id: toastId })
@@ -39,7 +46,7 @@ export async function exportMake(
 
   const params: components['schemas']['PrintParameters'] = {
     machine_id: machineId,
-    job_name: 'Exported Job', // TODO: make this the project name.
+    job_name: name,
   }
   try {
     console.log('params', params)

src/wasm-lib/Cargo.lock

@@ -121,9 +121,9 @@ dependencies = [
 
 [[package]]
 name = "anyhow"
-version = "1.0.89"
+version = "1.0.91"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "86fdf8605db99b54d3cd748a44c6d04df638eb5dafb219b135d0149bd0db01f6"
+checksum = "c042108f3ed77fd83760a5fd79b53be043192bb3b9dba91d8c574c0ada7850c8"
 dependencies = [
  "backtrace",
 ]
@@ -1684,9 +1684,9 @@ dependencies = [
 
 [[package]]
 name = "kittycad-modeling-cmds"
-version = "0.2.68"
+version = "0.2.70"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7e3aedfcc1d8ea9995ec3eb78a6743c585c9380475c48701797f107489b696aa"
+checksum = "b135696d07a4fab928e5abace4dd05f4976eafab5d73e5747a85dc5a684b936c"
 dependencies = [
  "anyhow",
  "chrono",
@@ -3005,9 +3005,9 @@ dependencies = [
 
 [[package]]
 name = "serde_json"
-version = "1.0.128"
+version = "1.0.132"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6ff5456707a1de34e7e37f2a6fd3d3f808c318259cbd01ab6377795054b483d8"
+checksum = "d726bfaff4b320266d395898905d0eba0345aae23b54aee3a737e260fd46db03"
 dependencies = [
  "indexmap 2.6.0",
  "itoa",

src/wasm-lib/Cargo.toml

@@ -72,7 +72,7 @@ members = [
 [workspace.dependencies]
 http = "1"
 kittycad = { version = "0.3.23", default-features = false, features = ["js", "requests"] }
-kittycad-modeling-cmds = { version = "0.2.68", features = ["websocket"] }
+kittycad-modeling-cmds = { version = "0.2.70", features = ["websocket"] }
 
 [[test]]
 name = "executor"

src/wasm-lib/kcl-macros/tests/macro_test.rs

@@ -12,7 +12,7 @@ fn basic() {
     let expected = Program {
         start: 0,
         end: 11,
-        body: vec![BodyItem::VariableDeclaration(VariableDeclaration {
+        body: vec![BodyItem::VariableDeclaration(Box::new(VariableDeclaration {
             start: 0,
             end: 11,
             declarations: vec![VariableDeclarator {
@@ -36,7 +36,7 @@ fn basic() {
             visibility: ItemVisibility::Default,
             kind: VariableKind::Const,
             digest: None,
-        })],
+        }))],
         non_code_meta: NonCodeMeta::default(),
         digest: None,
     };

src/wasm-lib/kcl/Cargo.toml

@@ -68,7 +68,7 @@ tokio-tungstenite = { version = "0.24.0", features = ["rustls-tls-native-roots"]
 tower-lsp = { version = "0.20.0", features = ["proposed"] }
 
 [features]
-default = ["engine"]
+default = ["engine"]  # add wasm-engine-utils here when we're ready
 cli = ["dep:clap"]
 # For the lsp server, when run with stdout for rpc we want to disable println.
 # This is used for editor extensions that use the lsp server.
@@ -77,6 +77,10 @@ engine = []
 pyo3 = ["dep:pyo3"]
 # Helper functions also used in benchmarks.
 lsp-test-util = []
+#if enabled, kcl will link directly against a wasm build of the engine utils lib to save latency
+wasm-engine-utils = []
+#if enabled, kcl will link directly against a native build of the engine utils lib to save latency (not yet functional)
+native-engine-utils = []
 
 tabled = ["dep:tabled"]
 

src/wasm-lib/kcl/src/ast/types.rs

@@ -454,7 +454,7 @@ pub(crate) use impl_value_meta;
 pub enum BodyItem {
     ImportStatement(Box<ImportStatement>),
     ExpressionStatement(ExpressionStatement),
-    VariableDeclaration(VariableDeclaration),
+    VariableDeclaration(Box<VariableDeclaration>),
     ReturnStatement(ReturnStatement),
 }
 
@@ -2719,7 +2719,7 @@ pub struct FunctionExpression {
 impl_value_meta!(FunctionExpression);
 
 #[derive(Debug, PartialEq, Clone)]
-pub struct RequiredParamAfterOptionalParam(pub Parameter);
+pub struct RequiredParamAfterOptionalParam(pub Box<Parameter>);
 
 impl std::fmt::Display for RequiredParamAfterOptionalParam {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
@@ -2751,7 +2751,7 @@ impl FunctionExpression {
             if param.optional {
                 found_optional = true;
             } else if found_optional {
-                return Err(RequiredParamAfterOptionalParam(param.clone()));
+                return Err(RequiredParamAfterOptionalParam(Box::new(param.clone())));
             }
         }
         let boundary = self.params.partition_point(|param| !param.optional);

src/wasm-lib/kcl/src/ast/types/execute.rs

@@ -551,13 +551,13 @@ impl ArrayRangeExpression {
             .execute_expr(&self.start_element, exec_state, &metadata, StatementKind::Expression)
             .await?
             .get_json_value()?;
-        let start = parse_json_number_as_u64(&start, (&*self.start_element).into())?;
+        let start = parse_json_number_as_i64(&start, (&*self.start_element).into())?;
         let metadata = Metadata::from(&*self.end_element);
         let end = ctx
             .execute_expr(&self.end_element, exec_state, &metadata, StatementKind::Expression)
             .await?
             .get_json_value()?;
-        let end = parse_json_number_as_u64(&end, (&*self.end_element).into())?;
+        let end = parse_json_number_as_i64(&end, (&*self.end_element).into())?;
 
         if end < start {
             return Err(KclError::Semantic(KclErrorDetails {
@@ -603,9 +603,9 @@ impl ObjectExpression {
     }
 }
 
-pub fn parse_json_number_as_u64(j: &serde_json::Value, source_range: SourceRange) -> Result<u64, KclError> {
+fn parse_json_number_as_i64(j: &serde_json::Value, source_range: SourceRange) -> Result<i64, KclError> {
     if let serde_json::Value::Number(n) = &j {
-        n.as_u64().ok_or_else(|| {
+        n.as_i64().ok_or_else(|| {
             KclError::Syntax(KclErrorDetails {
                 source_ranges: vec![source_range],
                 message: format!("Invalid integer: {}", j),

src/wasm-lib/kcl/src/engine/engine_utils.rs

@@ -0,0 +1,57 @@
+//! Functions for calling into the engine-utils library (a set of C++ utilities containing various logic for client-side CAD processing)
+//! Note that this binary may not be available to all builds of kcl, so fallbacks that call the engine API should be implemented
+
+use crate::{
+    errors::{KclError, KclErrorDetails},
+    std::Args,
+};
+use anyhow::Result;
+use std::ffi::{CString, CStr};
+use kittycad_modeling_cmds::{length_unit::LengthUnit, shared::Point3d};
+
+mod cpp {
+    use std::os::raw::c_char;
+
+    extern "C" {
+        pub fn kcEngineUtilsEvaluatePath(sketch: *const c_char, t: f64) -> *const c_char;
+    }
+}
+
+
+pub fn is_available() -> bool {
+    true
+}
+
+pub async fn get_true_path_end_pos(sketch: String, args: &Args) -> Result<Point3d<LengthUnit>, KclError> {
+    let c_string = CString::new(sketch).map_err(|e| {
+        KclError::Internal(KclErrorDetails {
+            message: format!("{:?}", e),
+            source_ranges: vec![args.source_range],
+        })
+    })?;
+    let arg = c_string.into_raw();
+    let result_string: String;
+
+    unsafe {
+        let result = cpp::kcEngineUtilsEvaluatePath(arg, 1.0);
+        let result_cstr = CStr::from_ptr(result);
+        let str_slice: &str = result_cstr.to_str().map_err(|e| {
+            KclError::Internal(KclErrorDetails {
+                message: format!("{:?}", e),
+                source_ranges: vec![args.source_range],
+            })
+        })?;
+        let str_buf: String = str_slice.to_owned();    
+        result_string = str_buf.clone();
+        let _ = CString::from_raw(arg);
+    }
+
+    let point: Point3d<f64> = serde_json::from_str(&result_string).map_err(|e| {
+        KclError::Type(KclErrorDetails {
+            message: format!("Failed to path position from json: {}", e),
+            source_ranges: vec![args.source_range],
+        })
+    })?;
+    
+    Ok(Point3d::<f64>::from(point).map(LengthUnit))
+}

src/wasm-lib/kcl/src/engine/engine_utils_api.rs

@@ -0,0 +1,35 @@
+//! Functions for calling into the engine-utils library (a set of C++ utilities containing various logic for client-side CAD processing)
+//! Note that this binary may not be available to all builds of kcl, so fallbacks that call the engine API should be implemented
+
+use crate::{
+    errors::{KclError, KclErrorDetails},
+    std::Args,
+};
+use crate::engine::kcmc::{each_cmd as mcmd, ModelingCmd};
+use anyhow::Result;
+use kittycad_modeling_cmds::{length_unit::LengthUnit, ok_response::OkModelingCmdResponse, shared::Point3d, websocket::OkWebSocketResponseData};
+
+pub fn is_available() -> bool {
+    true
+}
+
+pub async fn get_true_path_end_pos(sketch: String, args: &Args) -> Result<Point3d<LengthUnit>, KclError> {
+    let id = uuid::Uuid::new_v4();
+    
+    let resp = args.send_modeling_cmd(id, ModelingCmd::from(mcmd::EngineUtilEvaluatePath {
+        path_json: sketch,
+        t: 1.0,
+    })).await?;
+
+    let OkWebSocketResponseData::Modeling {
+        modeling_response: OkModelingCmdResponse::EngineUtilEvaluatePath(point),
+    } = &resp 
+    else {
+        return Err(KclError::Engine(KclErrorDetails {
+            message: format!("mcmd::EngineUtilEvaluatePath response was not as expected: {:?}", resp),
+            source_ranges: vec![args.source_range],
+        }));
+    };
+
+    Ok(point.pos)
+}

src/wasm-lib/kcl/src/engine/engine_utils_wasm.rs

@@ -0,0 +1,56 @@
+//! Functions for calling into the engine-utils library (a set of C++ utilities containing various logic for client-side CAD processing)
+//! Note that this binary may not be available to all builds of kcl, so fallbacks that call the engine API should be implemented
+
+use crate::{
+    errors::{KclError, KclErrorDetails},
+    std::Args,
+};
+use anyhow::Result;
+use kittycad_modeling_cmds::{length_unit::LengthUnit, shared::Point3d};
+mod cpp {
+    use wasm_bindgen::prelude::wasm_bindgen;
+
+    #[wasm_bindgen(module = "/../../lib/engineUtils.ts")]
+    extern "C" {
+        #[wasm_bindgen(js_name = getTruePathEndPos, catch)]
+        pub fn get_true_path_end_pos(sketch: String) -> Result<js_sys::Promise, js_sys::Error>;
+    }
+}
+
+pub fn is_available() -> bool {
+    true
+}
+
+async fn call_cpp<F>(args: &Args, f: F) -> Result<String, KclError>
+where
+    F: FnOnce() -> Result<js_sys::Promise, js_sys::Error>,
+{
+    let promise = f().map_err(|e| {
+        KclError::Internal(KclErrorDetails {
+            message: format!("{:?}", e),
+            source_ranges: vec![args.source_range],
+        })
+    })?;
+
+    let result = crate::wasm::JsFuture::from(promise).await.map_err(|e| {
+        KclError::Internal(KclErrorDetails {
+            message: format!("{:?}", e),
+            source_ranges: vec![args.source_range],
+        })
+    })?;
+
+    Ok(result.as_string().unwrap_or_default())
+}
+
+pub async fn get_true_path_end_pos(sketch: String, args: &Args) -> Result<Point3d<LengthUnit>, KclError> {
+    let result_str = call_cpp(args, || cpp::get_true_path_end_pos(sketch.into())).await?;
+
+    let point: Point3d<f64> = serde_json::from_str(&result_str).map_err(|e| {
+        KclError::Type(KclErrorDetails {
+            message: format!("Failed to path position from json: {}", e),
+            source_ranges: vec![args.source_range],
+        })
+    })?;
+
+    Ok(Point3d::<f64>::from(point).map(LengthUnit))
+}

src/wasm-lib/kcl/src/engine/mod.rs

@@ -8,6 +8,17 @@ pub mod conn_mock;
 #[cfg(feature = "engine")]
 pub mod conn_wasm;
 
+#[cfg(not(target_arch = "wasm32"))]
+#[cfg(feature = "native-engine-utils")]
+pub mod engine_utils;
+#[cfg(target_arch = "wasm32")]
+#[cfg(feature = "wasm-engine-utils")]
+pub mod engine_utils_wasm;
+
+#[cfg(feature = "engine")]
+#[cfg(any(not(target_arch = "wasm32"), all(not(feature = "native-engine-utils"), not(feature = "wasm-engine-utils"))))]
+pub mod engine_utils_api;
+
 use std::{
     collections::HashMap,
     sync::{Arc, Mutex},

src/wasm-lib/kcl/src/executor.rs

@@ -1601,6 +1601,19 @@ pub enum Path {
         #[serde(flatten)]
         base: BasePath,
     },
+    /// An arc (only used for engine-utils arg serialization for now)
+    Arc {
+        #[serde(flatten)]
+        base: BasePath,
+        /// angle range
+        #[ts(type = "[number, number]")]
+        angle_range: [f64; 2],
+        /// center
+        #[ts(type = "[number, number]")]
+        center: [f64; 2],
+        /// the arc's radius
+        radius: f64,
+    },
     /// A arc that is tangential to the last path segment that goes to a point
     TangentialArcTo {
         #[serde(flatten)]
@@ -1620,6 +1633,10 @@ pub enum Path {
         center: [f64; 2],
         /// arc's direction
         ccw: bool,
+        /// the arc's radius
+        radius: f64,
+        /// the arc's angle offset
+        offset: f64,
     },
     // TODO: consolidate segment enums, remove Circle. https://github.com/KittyCAD/modeling-app/issues/3940
     /// a complete arc
@@ -1668,6 +1685,7 @@ impl Path {
             Path::TangentialArcTo { base, .. } => base.geo_meta.id,
             Path::TangentialArc { base, .. } => base.geo_meta.id,
             Path::Circle { base, .. } => base.geo_meta.id,
+            Path::Arc { base, .. } => base.geo_meta.id,
         }
     }
 
@@ -1680,6 +1698,7 @@ impl Path {
             Path::TangentialArcTo { base, .. } => base.tag.clone(),
             Path::TangentialArc { base, .. } => base.tag.clone(),
             Path::Circle { base, .. } => base.tag.clone(),
+            Path::Arc { base, .. } => base.tag.clone(),
         }
     }
 
@@ -1692,6 +1711,7 @@ impl Path {
             Path::TangentialArcTo { base, .. } => base,
             Path::TangentialArc { base, .. } => base,
             Path::Circle { base, .. } => base,
+            Path::Arc { base, .. } => base,
         }
     }
 
@@ -1704,6 +1724,7 @@ impl Path {
             Path::TangentialArcTo { base, .. } => Some(base),
             Path::TangentialArc { base, .. } => Some(base),
             Path::Circle { base, .. } => Some(base),
+            Path::Arc { base, .. } => Some(base),
         }
     }
 }

src/wasm-lib/kcl/src/parser/parser_impl.rs

@@ -1342,7 +1342,7 @@ fn declaration_keyword(i: TokenSlice) -> PResult<(VariableKind, Token)> {
 }
 
 /// Parse a variable/constant declaration.
-fn declaration(i: TokenSlice) -> PResult<VariableDeclaration> {
+fn declaration(i: TokenSlice) -> PResult<Box<VariableDeclaration>> {
     let (visibility, visibility_token) = opt(terminated(item_visibility, whitespace))
         .parse_next(i)?
         .map_or((ItemVisibility::Default, None), |pair| (pair.0, Some(pair.1)));
@@ -1404,7 +1404,7 @@ fn declaration(i: TokenSlice) -> PResult<VariableDeclaration> {
     .map_err(|e| e.cut())?;
 
     let end = val.end();
-    Ok(VariableDeclaration {
+    Ok(Box::new(VariableDeclaration {
         start,
         end,
         declarations: vec![VariableDeclarator {
@@ -1417,7 +1417,7 @@ fn declaration(i: TokenSlice) -> PResult<VariableDeclaration> {
         visibility,
         kind,
         digest: None,
-    })
+    }))
 }
 
 impl TryFrom<Token> for Identifier {

src/wasm-lib/kcl/src/std/extrude.rs

@@ -256,6 +256,7 @@ pub(crate) async fn do_post_extrude(
                         });
                         Some(extrude_surface)
                     }
+                    Path::Arc { .. } => todo!(),
                 }
             } else if args.ctx.is_mock() {
                 // Only pre-populate the extrude surface if we are in mock mode.

src/wasm-lib/kcl/src/std/sketch.rs

@@ -6,7 +6,7 @@ use anyhow::Result;
 use derive_docs::stdlib;
 use kcmc::shared::Point2d as KPoint2d; // Point2d is already defined in this pkg, to impl ts_rs traits.
 use kcmc::{each_cmd as mcmd, length_unit::LengthUnit, shared::Angle, ModelingCmd};
-use kittycad_modeling_cmds as kcmc;
+use kittycad_modeling_cmds::{self as kcmc, units};
 use kittycad_modeling_cmds::shared::PathSegment;
 use parse_display::{Display, FromStr};
 use schemars::JsonSchema;
@@ -21,13 +21,26 @@ use crate::{
     },
     std::{
         utils::{
-            arc_angles, arc_center_and_end, get_tangent_point_from_previous_arc, get_tangential_arc_to_info,
+            arc_angles, arc_center_and_end, arc_start_center_and_end, get_tangent_point_from_previous_arc,
-            get_x_component, get_y_component, intersection_with_parallel_line, TangentialArcInfoInput,
+            get_tangential_arc_to_info, get_x_component, get_y_component, intersection_with_parallel_line,
+            TangentialArcInfoInput,
         },
         Args,
     },
 };
 
+#[cfg(not(target_arch = "wasm32"))]
+#[cfg(feature = "native-engine-utils")]
+use crate::engine::engine_utils;
+
+#[cfg(target_arch = "wasm32")]
+#[cfg(feature = "wasm-engine-utils")]
+use crate::engine::engine_utils_wasm as engine_utils;
+
+#[cfg(feature = "engine")]
+#[cfg(any(not(target_arch = "wasm32"), all(not(feature = "native-engine-utils"), not(feature = "wasm-engine-utils"))))]
+use crate::engine::engine_utils_api as engine_utils;
+
 /// A tag for a face.
 #[derive(Debug, Clone, Deserialize, Serialize, PartialEq, ts_rs::TS, JsonSchema)]
 #[ts(export)]
@@ -1495,7 +1508,45 @@ pub(crate) async fn inner_arc(
         } => {
             let a_start = Angle::from_degrees(*angle_start);
             let a_end = Angle::from_degrees(*angle_end);
-            let (center, end) = arc_center_and_end(from, a_start, a_end, *radius);
+
+            let (_, center, mut end) = arc_start_center_and_end(from, a_start, a_end, *radius);
+
+            if engine_utils::is_available() {
+                let mut path_plus_arc = sketch.clone();
+                let to = [0.0, 0.0];
+                let arc = Path::Arc {
+                    base: BasePath {
+                        from: from.into(),
+                        to,
+                        tag: None,
+                        geo_meta: GeoMeta {
+                            id: uuid::Uuid::new_v4(),
+                            metadata: args.source_range.into(),
+                        },
+                    },
+                    angle_range: [*angle_start, *angle_end],
+                    center: [center.x, center.y],
+                    radius: *radius,
+                };
+
+                path_plus_arc.value.push(arc);
+
+                let sketch_json_value = serde_json::to_string(&path_plus_arc).map_err(|e| {
+                    KclError::Type(KclErrorDetails {
+                        message: format!("Failed to convert sketch to json: {}", e),
+                        source_ranges: vec![args.source_range],
+                    })
+                })?;
+
+                //???? someone double check me on this unit conversion - mike
+                let units = units::UnitLength::Millimeters;
+                let result_end = engine_utils::get_true_path_end_pos(sketch_json_value, &args).await?;
+                end = Point2d { 
+                    x: result_end.x.to_millimeters(units),
+                    y: result_end.y.to_millimeters(units),
+                };
+            }
+
             (center, a_start, a_end, *radius, end)
         }
         ArcData::CenterToRadius { center, to, radius } => {
@@ -1616,7 +1667,7 @@ async fn inner_tangential_arc(
 
     let id = exec_state.id_generator.next_uuid();
 
-    let (center, to, ccw) = match data {
+    let (center, to, ccw, radius, offset) = match data {
         TangentialArcData::RadiusAndOffset { radius, offset } => {
             // KCL stdlib types use degrees.
             let offset = Angle::from_degrees(offset);
@@ -1654,13 +1705,15 @@ async fn inner_tangential_arc(
                 }),
             )
             .await?;
-            (center, to.into(), ccw)
+            (center, to.into(), ccw, radius, offset)
         }
     };
 
     let current_path = Path::TangentialArc {
         ccw,
         center: center.into(),
+        radius,
+        offset: offset.to_degrees(),
         base: BasePath {
             from: from.into(),
             to,

src/wasm-lib/kcl/src/std/utils.rs

@@ -221,6 +221,33 @@ pub fn arc_center_and_end(from: Point2d, start_angle: Angle, end_angle: Angle, r
     (center, end)
 }
 
+pub fn arc_start_center_and_end(
+    from: Point2d,
+    start_angle: Angle,
+    end_angle: Angle,
+    radius: f64,
+) -> (Point2d, Point2d, Point2d) {
+    let start_angle = start_angle.to_radians();
+    let end_angle = end_angle.to_radians();
+
+    let center = Point2d {
+        x: -1.0 * (radius * start_angle.cos() - from.x),
+        y: -1.0 * (radius * start_angle.sin() - from.y),
+    };
+
+    let start = Point2d {
+        x: center.x + radius * start_angle.cos(),
+        y: center.y + radius * start_angle.sin(),
+    };
+
+    let end = Point2d {
+        x: center.x + radius * end_angle.cos(),
+        y: center.y + radius * end_angle.sin(),
+    };
+
+    (start, center, end)
+}
+
 pub fn arc_angles(
     from: Point2d,
     to: Point2d,

src/wasm-lib/kcl/src/walk/ast_walk.rs

@@ -290,7 +290,7 @@ where
             walk_value(&xs.expression, f)
         }
         BodyItem::VariableDeclaration(vd) => {
-            if !f.walk(vd.into())? {
+            if !f.walk(vd.as_ref().into())? {
                 return Ok(false);
             }
             for dec in &vd.declarations {

src/wasm-lib/rust-toolchain.toml

@@ -1,3 +1,3 @@
 [toolchain]
-channel = "1.81.0"
+channel = "1.82.0"
 components = ["clippy", "rustfmt"]

src/wasm-lib/tests/executor/inputs/no_visuals/array_range_negative_expr.kcl

@@ -1,3 +1,2 @@
-xs = [-5..5]
+xs = [int(-5)..5]
 assertEqual(xs[0], -5, 0.001, "first element is -5")
-assert(false)

src/wasm-lib/tests/executor/no_visuals.rs

@@ -101,7 +101,7 @@ gen_test!(property_of_object);
 gen_test!(index_of_array);
 gen_test!(comparisons);
 gen_test!(array_range_expr);
-gen_test_fail!(array_range_negative_expr, "syntax: Invalid integer: -5.0");
+gen_test!(array_range_negative_expr);
 gen_test_fail!(
     invalid_index_str,
     "semantic: Only integers >= 0 can be used as the index of an array, but you're using a string"

vite.config.ts

@@ -58,6 +58,7 @@ const config = defineConfig({
   resolve: {
     alias: {
       '@kittycad/codemirror-lsp-client': '/packages/codemirror-lsp-client/src',
+      '@engine-utils': '/src/lib/engine-utils/engine.js',
     },
   },
   plugins: [react(), viteTsconfigPaths(), eslint(), version(), lezer()],